P507: AGREEMENT BETWEEN REAL-WORLD PHYSICIAN RESPONSE ASSESSMENT AND THE 2017 EUROPEAN LEUKEMIANET (ELN) CRITERIA IN ACUTE MYELOID LEUKEMIA (AML): A COMPARATIVE ANALYSIS
Authors: P. A. Patel, F. Hoff, A. J. Belli, E. Hansen, C. Anderson, A. Barcellos, L. L. Fernandes, H. Foss, M. He, M. Schulte, C.-K. Wang
Journal: HemaSphere (2022)

Background: Real-world data (RWD) is a valuable resource to understand the experience of oncology patients treated outside a clinical trial. Increasingly, RWD is being used in support of regulatory decision-making to evaluate outcomes compared to what is observed in clinical trials. In the real-world setting, physicians often do not utilize the specific inclusion/exclusion criteria and objective response criteria that are implemented in clinical trials. Rather, a descriptive assessment of response and clinical benefit is often used. Additionally, response assessment frequency may not adhere to the requirements from clinical trials. Subsequently, it is critical that real-world, physician-assessed responses are investigated to understand the concordance with objective criteria in order to contextualize endpoints reported using RWD. Aims: To evaluate the concordance and performance of physician-assessed response in the COTA real-world database to derived response using the 2017 ELN criteria as the established standard for response assessment in clinical trials. Methods: A total of 879 patients meeting the following criteria were identified in the COTA database: diagnosed with AML on or after April 1st, 2017, age ≥18 years at diagnosis, received systemic treatment after diagnosis, and had at least 28 days of follow up or a post-therapy bone marrow assessment. The COTA database is a USA-based dataset composed of longitudinal, de-identified data on the diagnosis, clinical management, and outcomes of patients with cancer. Physician-assessed response was manually captured as documented in electronic health records (EHRs). Derived response was defined as 2017 ELN response based on bone marrow findings and complete blood count (CBC) results available in the EHR. Rates of agreement and disagreement between physician-assessed and derived response to first line treatment were calculated. Overall response rate (ORR) was estimated by both response definitions. Results: The study population (n=879) had a median age of 67 years and were predominately white (78%), treated in the community setting (65%), and adverse risk per ELN criteria (42%). Overall agreement between response categories was 65.1% with the highest agreement among CR (61.7%). Agreement by response category is shown in Table 1. In a selected group of patients with all required bone marrow and lab values to derive ELN response (n=435), the ORR (95% confidence interval) was 80.5% (76.4, 84.1) for derived responders and 79.1% (75, 82.8) for physician-assessed responders. Image:Summary/Conclusion: In our real-world cohort of patients with AML, agreement between derived response per 2017 ELN criteria and physician-assessed response was 65.1%. Among patients with derivable ELN response, the ORR calculations were similar by both response definitions. These findings are significant in showing that responses assessed by physicians treating patients with AML in the real-world setting are comparable to those derived via 2017 ELN criteria. Of interest, discordance in derived response vs. physician-assessed response was most common in the setting of CRi and MLFS. These two response types require the incorporation of CBC results and bone marrow cellularity. Future research will investigate the outcomes of patients with discordant response assessments and incorporate additional response categories including CR with partial hematologic recovery (CRh) and CR without minimal residual disease (CR MRD-).